Shaving apparatus



Aug. 19, 1941.

w. T. WEIDENMAN SHAVING APPARATUS Filed Jan. 26, 1938 M Z5 f; 27 JO 2/ Z6 5 2/ 25 26 @974] lNVENTOR .ing during shaving.

UNlTED STATES PATENT OFFICE SHAVIN G APPARATUS William T. Weldenman, Spring Valley, N. Y., as-

signor to Telephonics Corporation, New York. N. Y., a corporation of New York Application January 26, 1938, Serial No. 186,914

6 Claims.

This invention relates to a shaving device of the power driven type and has particular reference to the so-called dry shaving devices which cut the hair to the level or surface of the skin without the necessity for employing lather or other preparations to facilitate the shaving operation.

Dry shaving devices operate in the fashion of hair clippers, that is, they embody a stationary shear plate provided with an aperture or slot, one edge of which acts as a blade between which and the cooperating edge of a moving inner cutter, either reciprocating or rotary, the hair is caught and sheared off, the cutter wiping the under surface of the shear plate in its movement.

1 The commercial dry shavers of this class generally take two forms, characterized by either a flat or by a rounded or cylindrical outer shear plate, and each form has certain operating advantages not found in the other. For example, the flat shear plate enables end-shearing across its entire width, and affords the principal advantage of protection against abrasion of the skin by the inner cutter teeth becausethe shear plate blades intervene. However, because the cutting is performed through the flat shear plate .it must be made so extremely thin to provide a tlose shave that it requires support against flexplate is flat, it cannot reach the hairs in the crevices without theuse of hair lifting shoes or a comb for guiding the hair in an erect position into the cutting zone of the inner cutter.

The round or cylindrical .outer shear plate tends to stretch the skin because of its curvature and thus erects the hair for side shearing plate forms of dry shaving devices, all or most of the hair shearing is effected at the line of juncture of the leading edges of outer shear plate blades and the cutter teeth and that the amount of end cutting across the entire width of the flat shear plate is negligible, so that it is necessary to provide only a very narrow or substantially single line cutting zone.

Also because the shear In accordance with the present invention, a

dry-shaving device of the reciprocating inner cutter type is provided, which has a narrow cutting zone and combines the advantages of the round outer shear plate of skin-stretching and channel-shaped outer shear plate having an arched skin-engaging surface with a row oi.

transverse slots along each lateral side extending part way across the skin-contacting surface and part way down the side walls of the channel shear plate. The two rows of blades formed by these slots are accordingly separated by a non-cutting strip of substantial width extending longitudinally of the center of the skin-engaging surface and this strip is rendered more rigid by a rib extending longitudinally of the under surface of the shear plate and merging at its ends into transverse shoulders across the ends of the shear plate.

The blades on the shear plate are accordingly angle-shaped and are rigidly supported at their opposite ends by the non-cutting center strip and the sidewalls of the channel shear plate, thus enabling the blades to be reduced to extreme thinness at their apices, i. e. along the opposite lateral sides of the skin-engaging surface, without impairing their rigidity and without rendering them subject to flexing under abnormal shavlng pressures.

Positioned'within the inverted channel-shaped shear plate is a channel-shaped inner cutter, the upper longitudinal edges of the arms of which are serrated transversely to provide teeth cooperating with the blades of the shear plate at their thinnest points, so that, as the inner cutter is reciprocated by suitable power driven means, the hair shearing is effected only in a narrow zone along each opposite side of the skin-contacting surface of the shear plate, so that line-cutting results.

-It will be seen that, inasmuch as the shearing zone is confined to the leading side of the skincontacting surface of the shear plate as the latter is moved over the skin, the hairs are immediately attacked by the inner cutter, so that hair-guiding slots and hair-lifting shoes or comb become unnecessary, and this feature plus the skin-stretching feature of the arched skinengaging surface, provide the principal advantages of the usual round head shaving devices, whereas the protection against skin abrasion ably. the slots onopposite sides are staggered or displaced laterally, so that a blade 28 on one side-lies directly opposite a slot 22 on the other afforded by enclosure of the inner cutter'the shear plate teeth provides the principal advan-.

tage of the usual fiat head shaving device.

"The device may have one cutting side or two,

which are eifective when the device is moved in opposite directions and where two cutting sides .are employed, the slots forming the blades are displaced laterally on the opposite sides, so that a slot on one side is opposite a blade on the other side, whereby the hairs not cut by the 1 leading side. by reason of being covered by a side, as is illustratedin Fig. 3

The slots 22 may be formed by a saw-cutting operation across each opposite'edge of the shear plate body 11, thus providing the blades with a rectangular cross-section. The relatively sharp outer corners of the blades 25 are preferably rounded oil,- as indicated at 28, to prevent abrasion-of the skin during the shaving operation. The blades 25 are angle-shaped in transverse cross-section, as illustrated in Fig. 1, and

Y are rigidly supported at their opposite ends by vice of this invention, as seen along the line I Fig. 2 is an elevation of the operative portion of the shaving devi'ce,-shown in partial longitudinal section and with other portions of the shaving head. broken away to illustrate its construction; v

Fig. 3 is an enlarged fragmentary plan view of the skin-contacting surface thereof;

' the non-cutting center strip 24 and the side walls 2i of the shear plate body II and accordingly are inherently rigid. The center strip 24 is rendered especially rigid by an interior rib 21 extending coincidentally therewith longitudinally from end-to-end and merging at its opposite ends into the rigid transverse shoulders 22 at the ends of the shear plate body II; By reason of this rigid construction of the blades 2!, they may be uced to a thinness of a few thousandths of an ch at the longitudinal shearing line or zone 2! without impairing their rigidity, so that they Fig. 4 is an enlarged fragmentary elevation thereof and Fig. 5 is an enlarged fragmentary elevation of I the inner cutter, partially broken away.

Referring to Figs. 1 and 2 of the drawing, nu-

, meral l0 designates a handle, preferably of composition material containing'electro-motive means, such as a motor or vibrator for oscillating the lever I l pivoted at l2 on a suitable frame, such-as'the bar it anchored at its ends in the handle Ill. The lever projects through an aperture l4 in the base of the cutter head I! and engages the channel-shaped inner cutter I. for reciprocating it rapidly within the hollow shear plate body ll. The cutter head It is mounted in a slot at the upper. end of the handle ill and is locked in fixed position therein by a set screw II,

or the like.

The cutter head ll includes the hollow shear plate body l1 and the inner cutter It. The shear plate body I! comprises an inverted channel havdo not iiex'even under abnormal shaving pres- Bill? and cone uently require-naadditional supmr v It will be observed that the blades 25 rapidly increase in thickness to either side of the thin zone 29, due to the arch in the cylindrical skin- -contacting surface 20 on one side and the thickness of the side walls 2| on the other side. This thin zone 29 may be obtained by broaching or otherwise cutting out the metal after the outer shear plate body I! is shaped and slotted, thus providing'sharp cutting edges for the inner walls of the blades 25.

The longitudinal edges of the upstanding arms 20 and vthe channel-shaped inner cutter is are provided with spaced transverse slots 2i forming the cutting teeth :2, the teeth on the ing a longitudinally-arched or cylindrical skin- I contacting surface 20 and integral side walls 2| which converge downwardly as shownin Fig. 1 so that the cutter head II is generally keystoneshapedin cross-section. The lower ends of the side walls 2| are suitably secured to a spacer 22 providing the center aperture I4 for the oscillating lever II.

The opposite lateral sides of the shear plate body H are provided withspaced slots 23. which are of suiiicient width to allow the free passage of hairs but too narraw to admit the skin. The slots .22 extend only partially across the skin- ,contacting surface and partway down the side about half the overall width of the skin-contacting surface 20.

t The slots 22 accordingly form two opposite rows of blades 25 extending along both lateral sides of the skin-contacting surface 2.. Preferbody II, the corresponding opposite tooth 22 lies under a slot 22 on the opposite side of the shear plate body II. The inner cutter teeth 22 are spaced from center to center the same distance as'the blades 25 and are preferably slightly narrower than the latter, making the inner cutter slots 3| slightly wider .than the slots 23 of the shear plate body. Thus the inner cutter teeth 22 register with the blades 2|.

The innercutter teeth 22 are cutsquare or true at their outer corners 22', as by saw-cutting or precision milling of the slots 2!, so that when these outer corners 22' engage in the zone 22 of the shear plate body I! the desired narrow orline cutting zone at 29 is achieved. Prefera'bly, the inner cutter I8 is made of relatively thin resilient material with its arms 20 spread at a slightly greater divergence than the cooperating side walls 2l' of the shear plate body l1, so that when the inner cutter It is inserted within the shear plate body ll, its outer upper edges are urged into intimate frictional engagement with the upper inner surfaces of the shear plate body side walls 2|.

Also, the inner' cutter i6 is urged resiliently .outwardly with its teeth in intimate frictional a,as s,1se

the spacer 22 with their rounded upper ends in engagement with the lower surface of the inner cutter it. A spring 34 extending between bar cutter IS without obstruction by the plungers II.

In operation of the shavingdevice of this invention, the power means, such as the motor within handle i0, is placed in operation, causing lever I I to oscillate about its pivot l2 and rapidly reciprocate inner cutter I, so that its teeth 22 cooperate withthe edges of the blades 25 of the shear plate body l1, alternately covering and un covering slots 23. As the skin-contacting surface is moved back and forth over the skin in the direction of the slots 23, the arched or outwardlycurved cylindrical surface 20 thereof stretches the skin, so that the hairs enter the slots 23 in the leading edge in an erect position to be immediately severed at the narrow or line cutbetween the inner cutter teeth 32 and the skin so that abrasion by the inner cutter is prevented.

Because of the thinness of the shear plate body il along the shearing zone 28, a close shave is provided, the skin also being pressed slightly into the slots 23, so that the hairs are sheared at or below the normal skin level. Only light shaving pressure is necessary to obtain a close shave, but even if abnormal pressure is exercised, the blades ZU-cannot flex because of their inherently rigid structure, so that no support for them against flexure is required.

Because of the staggered relation of the blades on opposite sides of the shear plate body, those hairs which were not severed in one movement of the device in a right line over the skin by reason of being covered by the blades 25, are

sheared by the opposite side of the device when it is moved in the same line in the opposite direction, because the hairs can enter slots 23 opposite those blades 25 that formerly covered the plate and forming therewith a hollow body, a substantially channel-shaped movable cutter within said body having teeth along the edges of its upwardly-extending arms for cooperation with said blades, the said arms of said cutter being resiliently urged apart for intimate frictional engagement with the inner surfaces of said side walls, and means for reciprocating said cutter to shear hairs projected between said blades.

2. In a shaving device, the combination of an elongated skin-contacting plate having a convex outer surface and tapering, in thickness from its longitudinal center line to its opposite longitudinal sides, said sides being slotted transversely to provide two rows of opposite blades separated by an imperforate longitudinal center strip, integral walls converging'downwardly from the said opposite longitudinal sides of said plate, a movable cutter within said body having upwardly extendingand outwardly diverging arms, said arms having teeth-along their upper edges for cooperation with said blades, the said arms of said cutter being resiliently urged apart for intimate frictional engagement with the inner surfaces of said side walls, and means for reciprocating said cutter to shear hairs projected between said blades.

3. In a shaving device, the combination of a shaving head having a longitudinally extending rib, sets of blades of substantially triangular shape in vertical section extending laterally from the rib in opposite directions, depending side walls integral with the outer ends of said blades hairs, so that fewer passes over the skin are required to cut all the hairs. Although a twosided shaving device is illustrated, a one-sided device may be provided by using half of the structure described.

Itwill be seen that a very efllcient and simple dry shaving device is provided by this invention, having the enumerated advantages of those in current use while providing additional features contributing tomore effective and rapid shaving. While the foregoing description and accompanying drawing are illustrative of a preferred embodiment of the invention, it is to be understood that the invention is not limited thereby, but is susceptible of changes in form and detail within the scope of the appended claims.

I claim: I

1. In a shaving device, the combination of a substantially rectangular skin-contacting plate having transverse slots forming blades along the opposite longitudinal .sides of said plate separated by an imperforate center portion, walls depending from the said opposite sides of said 75' and converging downwardly to form with the blades and rib a hollow body, a cutter member in said body, said cutter member comprising a pair of upwardly divergingarms resiliently urged outwardly at a greater angle than the angle of the side walls, teeth on the upper edges of the arms bearing against the inner surfaces of said triangular blades and the inner surfaces of said side walls adjacent to said blades, and means for reciprocating said cutter member.

4. In a shaving device, the combination of a substantially rectangular skin-contacting plate reduced to extreme thinness along its opposite longitudinal sides, said opposite sides being slotted transversely to provide blades, a reinforcing rib extending longitudinally of said skin-contacting plate between said blades, substantially treme thinness along its opposite longitudinal sides and having a thickened reinforcing portion adJacent its center, said opposite sides being slotted transversely to provide blades, integral substantially flat extensions of said blades projecting downwardly from the thin sides of said skin-contacting plate and forming therewith a hollow body having inner and outercorner edges at the thinnest portions of said blades, a movable cutter within said body having a base spaced from said skin-contacting plate, side walls pro- Jecting upwardly from said base and notches 4 smarts in the'upper edges 01' said side walls forming teeth for cooperation with' said-blades, means for retaining said teeth in the said inner corner edges oi said hollow body and in engagement with the thin. portions of said blades, and means for reciprocating said cutter to shear hairs pro- Jected between said blades.

- 6. In a shavinggdevice, the combination of an elongated skin-contacting plate having a convex outer surface and tapering in thickness from 1 its longitudinal center line to its opposite longitudinal v side, said opposite sides being slotted transversely to provide two rows 01 blades sepa- WILLIAM T. WEIDENMAN. 

